jcl69cam

My 95 Z just started to sputter at slow speeds and the idle was between 450-550 rpms at a stop. When I accerellate from a stoplight it sputters, and then will clear and run fine. Seems to do well at highway speeds. Tryed to pull codes with my ALDL/USB cable but was unsuccessful. I'm getting voltage to the pink maf wire. Any suggestion. Thanks

mrmint69

Have you done any maintence on it recently or changed parts? Could be something simple like old plugs, air filter or maf dirty.

jcl69cam

Yea, I put LT headers on back in Feb, with new plugs and wires. I just cleaned the MAF today, but haven't had a chance to drive it.

mrmint69

Right after installing mine I was having have very similar issues. The car started running a little rougher, but only noticable at low rpm's. Turns out a plug wire was to close to the new headers and was slowly burning. I only caught it when it was really bad. I rechecked all my spark plugs and noticed one was not tight by a couple turns. It was the same way. Very hard to notice the performance most of the time. I found the best thing was to go over everything again to eliminate them.

jcl69cam

I drove the car today after cleaning the Maf. It ran better, but still stumbled at stoplights, and lower speeds. Did your SES light come on when you were having issues with your plugs? I'll recheck wires and plugs in the morning. Thanks.

Injuneer

There is no misfire detection in OBD-I. It was added with OBD-II in 96. Nor are their any diagnostics related to the high voltage side of the ignition. Hence, an SES is unlikely for burned wires or a loose plug.

Guest47904

Would expect a problem with ignition to get worse not better with speed/load. EGR is a common source of problems just off idle. Do you still have one?

mrmint69

I think the EGR will throw a code. Some codes don't turn the check engine light on. When my spark plug was loose it had a ticking sound, so that would be easy to notice with the hood open. Just go over the routing and placement of the wires. I bought the heat shields and it still ruined the plugs. I ended up using zip ties to keep them as far away as possible.

jcl69cam

Yes, I still have a EGR valve. The car runs great in the country, no missing or sputtering. As soon as I get into town and stop at a light, it starts idling bad, and will stumble as I take off and go thru the gears. As soon as I get up into the 2300 rpm range it cleans up and runs good. I can smell raw gas when it is acting up. Thanks

Injuneer

There is no code for the EGR sticking open slightly.

Guest47904

If it idles fine right after start up, the EGR is closed at that time. So pull the vac line off the EGR and plug it and take it for a ride.

jcl69cam

I plugged the EGR valve and the Vac line like you had stated Speedy. Drove the Z into town and it ran like its suppose to, no sputtering at all. So I guess new EGR is in store for Z. Thanks alot.